The present invention relates to an electronic hydraulic brake device, and more particularly, to an electronic hydraulic brake device capable of realizing the functions of a pedal simulator and a backup master cylinder through a single device.
In general, an electronic hydraulic brake device senses a driver's pedal pressure through a sensor and controls the brake pressure of each wheel using a hydraulic modulator.
The electronic hydraulic brake device includes a sensor and a pedal simulator. The sensor senses a stroke distance of a pedal so as to indicate brake pressure desired by a driver, and the pedal simulator causes the driver to feel the same pedal pressure as a general hydraulic brake device.
In a normal state, when the driver steps on the brake pedal, pressure is generated from a backup master cylinder and then transmitted to the pedal simulator, thereby providing a reaction feel to the driver.
A controller determines a brake force requested by the user through a pedal stroke sensor and a pressure sensor, and drives a main master cylinder to generate a brake force of a wheel brake.
Conventionally, the backup master cylinder and the pedal simulator have been separately provided. Thus, the device inevitably has a large size, and the productivity is degraded due to the increase in number of parts.
Furthermore, a process of injecting brake oil is separately performed in a production line, because the backup master cylinder and the pedal simulator are separately installed. Thus, since an additional device is needed, the maintenance cost is increased. Therefore, there is a demand for a system capable of solving the problems.
The related art of the present invention is disclosed in Korean Patent Laid-open Publication No. 2007-0104982 published on Oct. 30, 2007 and entitled “Control apparatus for valve in electro-hydraulic brake system”.